Fenomén trpasličích kmenů S. aureus, tzv. Small Colony Variants (SČV), je spojen s chronickými a rekurentními stafylokokovými infekcemi. Tyto fenotypové varianty se liší od kmenů S. aureus s běžným fenotypem nejčastěji velikostí kolonií, jejich morfologií, pigmentací a dalšími znaky, ale také molekulárně genetickými změnami. Příčinou vzniku SCV fenotypu je často mutace v některém z důležitých metabolických či regulačních genů, která je spojena s auxotrofií. Z klinického hlediska je významná zvýšená schopnost SCV kmenů odolávat antibiotické léčbě, zapříčiněná jednak rezistencí k určitým antibiotikům spojenou s příčinou SCV fenotypu a také se schopností těchto kmenů perzistovat uvnitř hostitelských buněk.

The phenomenon of dwarf colonies of S. aureus, the so-called small colony variants (SCVs), is associated with chronic and recurrent staphylococcal infections. Most frequently, these phenotypic variants differ from normal strains of S. aureus in colony size, morphology, pigmentation and other characteristics as well as molecular genetic changes. SCVs frequently emerge as a result of mutations in metabolically important and regulatory genes. The mutations are a cause of SCVs auxotrophy. From a clinical point of view, an increased ability of SCVs to resist antibiotic therapy and also an ability to persist within eukaryotic host cells are of importance.

• MeSH
• antibakteriální látky terapeutické užití   MeSH
• cystická fibróza farmakoterapie   mikrobiologie   MeSH
• fenotyp MeSH
• hemin MeSH
• kultivační techniky metody   statistika a číselné údaje   trendy   MeSH
• lidé MeSH
• molekulární biologie MeSH
• mutace genetika   MeSH
• stafylokokové infekce * diagnóza   etiologie   mikrobiologie   MeSH
• Staphylococcus aureus * izolace a purifikace   patogenita   MeSH
• vitamin K 3 metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH
• přehledy MeSH

KEY MESSAGE: Multiple origins of Indian dwarf wheat were due to two mutations targeting the same TREE domain of a GSK3-like kinase, and these mutations confer to enhanced drought tolerance and increased phosphate and nitrogen accumulation for adaptation to the dry climate of Indian and Pakistan. Indian dwarf wheat, featured by the short stature, erect leaves, dense spikes, and small, spherical grains, was a staple crop in India and Pakistan from the Bronze Age until the early 1900s. These morphological features are controlled by a single locus Sphaerococcum 1 (S1), but the genetic identity of the locus and molecular mechanisms underlying the selection of this wheat type are unknown. In this study, we showed that the origin of Indian dwarf wheat was due to two independent missense mutations targeting the conserved TREE domain of a GSK3-like kinase, which is homologous to the Arabidopsis BIN2 protein, a negative regulator in brassinosteroid signaling. The S1 protein is involved in brassinosteroid signaling by physical interaction with the wheat BES1/BZR1 proteins. The dwarf alleles are insensitive to brassinosteroid, upregulates brassinosteroid biosynthetic genes, significantly enhanced drought tolerance, facilitated phosphate accumulation, and increased high molecular weight glutenins. It is the enhanced drought tolerance and accumulation of nitrogen and phosphate that contributed to the adaptation of such a small-grain form of wheat to the dry climate of India and Pakistan. Thus, our research not only identified the genetic events underlying the origin of the Indian dwarf wheat, but also revealed the function of brassinosteroid in the regulation of drought tolerance, phosphate homeostasis, and grain quality.

• MeSH
• fenotyp MeSH
• fosfáty metabolismus   MeSH
• fosforylace MeSH
• geneticky modifikované rostliny genetika   fyziologie   MeSH
• kinasa 3 glykogensynthasy genetika   metabolismus   MeSH
• mutace * MeSH
• období sucha * MeSH
• pšenice genetika   fyziologie   MeSH
• regulace genové exprese u rostlin MeSH
• rostlinné proteiny genetika   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH

The genus Phodopus consists of three species--P. campbelli (Pc), P. sungorus (Ps), and P. roborovskii (Pr). They inhabit steppes, semi-deserts, and deserts in continental Asia with a climate changing from a moderate to a hard Continental one with extreme daily and seasonal variations. These different environmental challenges are likely to have consequences for hamsters' morphology, physiology, and behavior. Hamsters of all three species were investigated during the course of the year in the laboratory though using natural lighting and temperature conditions. Motor activity and body temperature were measured continuously, and body mass, testes size, and fur coloration every 1-2 weeks. With regard to the pattern of activity, nearly twice as many Pc as Ps hamsters (25 vs. 14%) failed to respond to changes of photoperiod, whereas all Pr hamsters did. Body mass and testes size were high in summer and low in winter, with the biggest relative change in Ps and the lowest in Pr hamsters. Changes of fur coloration were found in Ps hamsters only. All responding animals (that is excluding Pr), exhibited regular torpor bouts during the short winter days. In autumn, seasonal changes started considerably earlier in Ps hamsters. To investigate the putative causes of these different time courses, a further experiment was performed, to identify the critical photoperiod. Hamsters were kept for 10 weeks under different photoperiods, changing from 16 to 8 h light per day. Motor activity was recorded continuously, to identify responding and non-responding animals. Body mass was measured at the beginning and the end of the experiment, testes mass only at the end. The critical photoperiod was found to be similar in all three species. Though in a further experiment, Pc and Pr hamsters showed a delayed response, whereas the changes in Ps hamsters started immediately following transfer to short-day conditions. The results show that interspecific differences in seasonal adaptation exist, even between the closely related Ps and Pc hamsters, possibly due to different conditions in their natural habitat. Also, the impact of environmental factors like climatic conditions and food resources may differ between species.

• MeSH
• barva vlasů MeSH
• časové faktory MeSH
• cykly aktivity MeSH
• druhová specificita MeSH
• ekosystém * MeSH
• fotoperioda MeSH
• fyziologická adaptace MeSH
• křečci praví MeSH
• Phodopus růst a vývoj   fyziologie   MeSH
• pohybová aktivita MeSH
• roční období * MeSH
• tělesná hmotnost MeSH
• teplota MeSH
• termoregulace MeSH
• testis růst a vývoj   MeSH
• velikost orgánu MeSH
• vlasy, chlupy MeSH
• zvířata MeSH
• Check Tag
• křečci praví MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH

• MeSH
• dítě MeSH
• hypofyzární hormony nedostatek   MeSH
• hypofyzární nanismus farmakoterapie   genetika   MeSH
• lidé MeSH
• poruchy růstu farmakoterapie   genetika   MeSH
• růstový hormon nedostatek   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• kazuistiky MeSH

The applications of semi-dwarf genes such as sd1 and Rht1 in rice and wheat resulted in the first "green revolution" in the 1960s. However, such semi-dwarf genes that can efficiently reduce plant stature and have few negative yield traits have not yet been identified in maize. In this study, a new allele of Brachytic2 gene (qpa1) encoding P-glycoprotein was rapidly fine-mapped using a modified method. The qpa1, containing a 241-bp deletion in the last exon, had no negative effect on yield, but greatly modified the plant architecture including significantly reduced plant height and ear height, increased stalk diameter and erected leaf. A common variant similar to maize qpa1 was also present in the sorghum orthologous dw3 locus. Comparative RNA-seq analysis next showed 99 differentially co-expressed genes affected by Br2 in maize and dw3 in sorghum, including four plant height genes D3, BAK1, Actin7 and Csld1, which are involved in gibberellin and brassinosteroid biosynthesis, auxin transport and cellulose synthesis. The qpa1 can be applied to efficiently modify plant stature in maize and in combination with D3, BAK1, Actin7, Csld1 and the other 95 differentially co-expressed genes, can be edited using new genomic editing tools for further applications and studies.

• MeSH
• alely * MeSH
• chromozomy rostlin MeSH
• fenotyp * MeSH
• genetické asociační studie * MeSH
• genom rostlinný MeSH
• genomika metody   MeSH
• inbreeding MeSH
• kukuřice setá genetika   MeSH
• kvantitativní znak dědičný MeSH
• lokus kvantitativního znaku MeSH
• mapování chromozomů MeSH
• rostlinné geny * MeSH
• sekvenční analýza RNA MeSH
• šlechtění rostlin MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Phospholipids have recently been found to be integral elements of hormone signalling pathways. An Arabidopsis thaliana double mutant in two type III phosphatidylinositol-4-kinases (PI4Ks), pi4kIIIβ1β2, displays a stunted rosette growth. The causal link between PI4K activity and growth is unknown. Using microarray analysis, quantitative reverse transcription polymerase chain reaction (RT-qPCR) and multiple phytohormone analysis by LC-MS we investigated the mechanism responsible for the pi4kIIIβ1β2 phenotype. The pi4kIIIβ1β2 mutant accumulated a high concentration of salicylic acid (SA), constitutively expressed SA marker genes including PR-1, and was more resistant to Pseudomonas syringae. pi4kIIIβ1β2 was crossed with SA signalling mutants eds1 and npr1 and SA biosynthesis mutant sid2 and NahG. The dwarf phenotype of pi4kIIIβ1β2 rosettes was suppressed in all four triple mutants. Whereas eds1 pi4kIIIβ1β2, sid2 pi4kIIIβ1β2 and NahG pi4kIIIβ1β2 had similar amounts of SA as the wild-type (WT), npr1pi4kIIIβ1β2 had more SA than pi4kIIIβ1β2 despite being less dwarfed. This indicates that PI4KIIIβ1 and PI4KIIIβ2 are genetically upstream of EDS1 and need functional SA biosynthesis and perception through NPR1 to express the dwarf phenotype. The slow root growth phenotype of pi4kIIIβ1β2 was not suppressed in any of the triple mutants. The pi4kIIIβ1β2 mutations together cause constitutive activation of SA signalling that is responsible for the dwarf rosette phenotype but not for the short root phenotype.

• MeSH
• 1-fosfatidylinositol-4-kinasa genetika   metabolismus   MeSH
• Arabidopsis anatomie a histologie   enzymologie   genetika   růst a vývoj   MeSH
• down regulace genetika   MeSH
• fenotyp MeSH
• genom rostlinný MeSH
• genotyp MeSH
• kinetika MeSH
• kořeny rostlin anatomie a histologie   růst a vývoj   MeSH
• kyselina salicylová metabolismus   MeSH
• listy rostlin genetika   růst a vývoj   MeSH
• metabolismus lipidů genetika   MeSH
• modely genetické MeSH
• mutace genetika   MeSH
• nemoci rostlin genetika   imunologie   mikrobiologie   MeSH
• odolnost vůči nemocem genetika   imunologie   MeSH
• proteiny huseníčku genetika   metabolismus   MeSH
• Pseudomonas fyziologie   MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• regulace genové exprese u rostlin MeSH
• signální transdukce MeSH
• upregulace genetika   MeSH
• výhonky rostlin růst a vývoj   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• MeSH
• dítě MeSH
• fenotyp MeSH
• homeodoménové proteiny genetika   MeSH
• hypofýza růst a vývoj   metabolismus   MeSH
• hypofyzární nanismus genetika   metabolismus   patofyziologie   MeSH
• jaderné proteiny genetika   MeSH
• lidé MeSH
• lidský růstový hormon genetika   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mutace * MeSH
• mutační analýza DNA MeSH
• předškolní dítě MeSH
• prospektivní studie MeSH
• protein Gli2 s motivem zinkových prstů genetika   MeSH
• proteiny s homeodoménou LIM genetika   MeSH
• receptory hormonů regulujících hypofyzární hormony MeSH
• receptory neuropeptidů MeSH
• transkripční faktor Pit-1 genetika   MeSH
• transkripční faktory SOXB1 genetika   MeSH
• transkripční faktory genetika   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• pozorovací studie MeSH

The role of chromosome changes in speciation remains a debated topic, although demographic conditions associated with divergence should promote their appearance. We tested a potential relationship between chromosome changes and speciation by studying two Lake Whitefish (Coregonus clupeaformis) lineages that recently colonized postglacial lakes following allopatry. A dwarf limnetic species evolved repeatedly from the normal benthic species, becoming reproductively isolated. Lake Whitefish hybrids experience mitotic and meiotic instability, which may result from structurally divergent chromosomes. Motivated by this observation, we test the hypothesis that chromosome organization differs between Lake Whitefish species pairs using cytogenetics. While chromosome and fundamental numbers are conserved between the species (2n = 80, NF = 98), we observe extensive polymorphism of subtle karyotype traits. We describe intrachromosomal differences associated with heterochromatin and repetitive DNA, and test for parallelism among three sympatric species pairs. Multivariate analyses support the hypothesis that differentiation at the level of subchromosomal markers mostly appeared during allopatry. Yet we find no evidence for parallelism between species pairs among lakes, consistent with colonization effect or postcolonization differentiation. The reported intrachromosomal polymorphisms do not appear to play a central role in driving adaptive divergence between normal and dwarf Lake Whitefish. We discuss how chromosomal differentiation in the Lake Whitefish system may contribute to the destabilization of mitotic and meiotic chromosome segregation in hybrids, as documented previously. The chromosome structures detected here are still difficult to sequence and assemble, demonstrating the value of cytogenetics as a complementary approach to understand the genomic bases of speciation.

• MeSH
• chromozomy genetika   MeSH
• fenotyp MeSH
• heterochromatin genetika   MeSH
• jezera MeSH
• populační genetika * MeSH
• Salmonidae genetika   MeSH
• sympatrie * MeSH
• vznik druhů (genetika) * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Polar auxin transport (PAT) plays key roles in the regulation of plant growth and development. Flavonoids have been implicated in the inhibition of PAT. However, the active flavonoid derivative(s) involved in this process in vivo has not yet been identified. Here, we provide evidence that a specific flavonol bis-glycoside is correlated with shorter plant stature and reduced PAT. Specific flavonoid-biosynthetic or flavonoid-glycosylating steps were genetically blocked in Arabidopsis thaliana. The differential flavonol patterns established were analyzed by high-performance liquid chromatography (HPLC) and related to altered plant stature. PAT was monitored in stem segments using a radioactive [(3)H]-indole-3-acetic acid tracer. The flavonoid 3-O-glucosyltransferase mutant ugt78d2 exhibited a dwarf stature in addition to its altered flavonol glycoside pattern. This was accompanied by reduced PAT in ugt78d2 shoots. The ugt78d2-dependent growth defects were flavonoid dependent, as they were rescued by genetic blocking of flavonoid biosynthesis. Phenotypic and metabolic analyses of a series of mutants defective at various steps of flavonoid formation narrowed down the potentially active moiety to kaempferol 3-O-rhamnoside-7-O-rhamnoside. Moreover, the level of this compound was negatively correlated with basipetal auxin transport. These results indicate that kaempferol 3-O-rhamnoside-7-O-rhamnoside acts as an endogenous PAT inhibitor in Arabidopsis shoots.

• MeSH
• Arabidopsis růst a vývoj   metabolismus   MeSH
• biologický transport MeSH
• fenotyp MeSH
• kempferoly metabolismus   fyziologie   MeSH
• kyseliny indoloctové metabolismus   MeSH
• výhonky rostlin genetika   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Reduced plant height and culm robustness are quantitative characteristics important for assuring cereal crop yield and quality under adverse weather conditions. A very limited number of short-culm mutant alleles were introduced into commercial crop cultivars during the Green Revolution. We identified phenotypic traits, including sturdy culm, specific for deficiencies in brassinosteroid biosynthesis and signaling in semidwarf mutants of barley (Hordeum vulgare). This set of characteristic traits was explored to perform a phenotypic screen of near-isogenic short-culm mutant lines from the brachytic, breviaristatum, dense spike, erectoides, semibrachytic, semidwarf, and slender dwarf mutant groups. In silico mapping of brassinosteroid-related genes in the barley genome in combination with sequencing of barley mutant lines assigned more than 20 historic mutants to three brassinosteroid-biosynthesis genes (BRASSINOSTEROID-6-OXIDASE, CONSTITUTIVE PHOTOMORPHOGENIC DWARF, and DIMINUTO) and one brassinosteroid-signaling gene (BRASSINOSTEROID-INSENSITIVE1 [HvBRI1]). Analyses of F2 and M2 populations, allelic crosses, and modeling of nonsynonymous amino acid exchanges in protein crystal structures gave a further understanding of the control of barley plant architecture and sturdiness by brassinosteroid-related genes. Alternatives to the widely used but highly temperature-sensitive uzu1.a allele of HvBRI1 represent potential genetic building blocks for breeding strategies with sturdy and climate-tolerant barley cultivars.

• MeSH
• alely MeSH
• aminokyseliny MeSH
• brassinosteroidy metabolismus   MeSH
• fenotyp MeSH
• ječmen (rod) genetika   růst a vývoj   metabolismus   MeSH
• jedlá semena MeSH
• mapování chromozomů MeSH
• modely strukturální MeSH
• molekulární sekvence - údaje MeSH
• mutace MeSH
• počasí MeSH
• počítačová simulace MeSH
• regulace genové exprese u rostlin * MeSH
• sekvence nukleotidů MeSH
• sekvenční analýza DNA MeSH
• signální transdukce MeSH
• teplota MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH